Once I’ve Tested and I Get the Results, What Should I Do Next?
U.S. EPA offers the following guidance for Homeowners:
If screening measurement results are LESS THAN 4 Pci/L:
Follow up measurements are probably not required. If the screening measurements were made with closed house conditions prior to and during the testing period, there is relatively little chance that the radon concentration in the home will be greater than 4 Pci/L as an annual average.
If screening measurement results are 4 Pci/L OR HIGHER:
Take a Follow-up test to be sure. Follow up with either a long-term test or a second short-term test:
- A long-term test (any device placed for 91 days or longer) offers a better understanding of your year-round average radon level.
- A short-term test (any device placed for 2 to 90 days) is recommended if results are needed quickly.
Follow-up Testing
If the initial short-term test result is 10 pCi/L or higher, you should take a second short-term test follow-up test. The Average of the initial test and the follow-up test should be used as the basis for any decision to mitigate.
If the initial short-term test result is greater than 4 pCi/L AND less than 10 pCi/L, a long term follow-up test is recommended. Any decision to mitigate should be based on the long term follow-up test.
- Average Indoor Radon Level: 1.3 pCi/L
- Average Outdoor Radon Level: 0.4 pCi/L
Note: Homeowner is responsible for additional follow-up testing
Retesting is recommended with each change in ownership, structural alterations to the dwelling that changes the ventilation pattern, major cracks occurring in the foundation or nearby blasting or earthquakes, and after every two years.
